Steerable landing gear



Dec. 18, 1951 T. c. OLIVER STEERABLE LANDING GEAR 4 Sheets-Sheet 2 Filed Sept. 11, 1948 IN V EN TOR.

T0MA$ CARR/1.580 UUVER A TTORNE X Dec. 18, 1951 T. c. OLIVER 2,578,897

STEERABLE LANDING GEAR Filed Sept. 11, 1948 4 Sheets-Sheet 5 FIG.4

JNVEN TOR. TOMAS CARRILERO OLIVE/l ATTORNEY Dec. 18, 1951 T. c. OLIVER 2,578,897

STEERABLE LANDING GEAR Filed Sept. 11, 1948 4 Sheets-Sheet 4 FIG. 6

v JNVENTOR. TOHAS CARRILEROOLIVER ATTORNEY Patented Dec. 18, 1951 I UNITED STATES PATE OFFICE Application September 11, 1948, Serial No. 48,80

In Spain February 24, 1948 The present invention relates to landing gears for aircraft and, more particularly, to means for operatively linking the wheels of a conventional landing gear with the control mechanism which governs the rudder, ailerons, etc. of an aircraft.

An object of the invention is to provide means for controlling the movement of an aircraft on the ground in such manner that interference due to crosswinds will be minimized.

A related object of the invention is to provide means to facilitate take-off and landing by an aircraft on a one-runway field in the face of crosswinds.

Another object of the invention is to provide novel type of control means adapted to be used with any type of aircraft to facilitate taxiing, take-off and landing.

A further object of the invention is to provide mechanism for controlling the landing gear and immobilizing the ailerons during taxiing, v

Fig. 2 is a side elevation, partly in section,

taken on the line 22 of Fig. 1;

Fig. 3 is a rear view of the controls'and other parts of the mechanism, taken on the line 33 of Fig. 2;

Fig. 4 is a perspective side view of part of the landing gear proper;

Fig. 5 is a perspective view of a portion of the mechanism shown in Fig. 4; and

Fig. 6 is a cross section taken on the line 6-6 of Fig. 3.

Referring to the drawing, there are shown a pair of sprockets I, 2 fixed by any convenient means such as threads, bolts or keys (not shown) to a pair of shafts or control columns 3, 4, respectively, each carrying at its upper end a steering wheel II, I2, respectively. A cross bar I is provided with three elongated slots 8, 9 and II which serve for the displaceable mounting of the columns 3, t and of a short center shaft It, the latter carrying a sprocket I 3. Sprockets I, 2 and I4 are each provided with two sets or rows of teeth, the forward row of each sprocket being engaged by a closed chain 28 which inter- 2 connects the three sprockets. Slots 8, 9 and It permit adjustment of the tension of chain 28.

While the sprockets I and2 are fixedly held on their control columns, sprocket ii is freely rotatable on the shaft [3, being prevented from substantial axial displacement by the tension of chain 28 although, of course, any convenient additional securing means may beused. Likewise mounted on the shaft I3 for free rotation thereon is a sprocket 16 provided with a single row of teeth. Sprocket I6 is provided on one of its faces with a channeled projectioniil into the, channel of which enters an extremity of a forked lever 2.5 which is pivoted at 28a (Fig. 2) to the control stick 20 whose head I9 is fixedly secured, as by means of a washer Hot and a nut I3b, to the free end of shaft I3. The other extremity of thelever 26 is provided with an operating knob 21.

The face of sprocket l6 opposite projection 25 is provided with aseries of lugs l5 adapted to cooperate with a series of depressions I30. pro vided in the adjacent face of sprocket I4, and the face of projection 25 is provided with similar lugs I'I fitting into depressions I8 provided on the adjacent face of head I9. Thus, by manipulating the lever 26 for axial displacement of the sprocket I6 in one direction or the other, the latter may be associated either with the sprocket It for rotative entrainment thereby or with the head I9 for immobilization with respect to" the shaft I3.

As best seen in Figs. 2 and 6, another washer I 3a and nut I3b may serve to secure the shaft I3 directly to the cross bar I at the center slot I0 of the latter; columns 3 and 4-, on the other hand, are supported on respective rods or axes 5, 6 the threaded ends of which, in turn, pass through slots 8, 9, respectively, and are secured to the bar I by means such as washers and nuts similar to the elements I3a, I31).

The free end of the stick 20 is provided with a bore 2| through which passes a pin 21a serving as a pivot for the entire assembly 3, t, 1, I3 and 20. The pin 2 Ia is suitably secured to the frame of the aircraft, shown in dot-dash outlines in Fig. 1.

The other (rearward) rows of teeth of sprocksecured to the frame by being rotatable about a pivot 5|a (Fig. 4). Similarly, the ends of chain are connected with a pair of wires or cables conducted over sets of rollers to operate another section of the retractable landing gear comprising a sleeve 38 as well as a supporting rod 5| and a wheel 53. The other'extremities of cables 32 and 33 are connected, respectively, with the ends of other open chains indicated in Fig. 1 at 3,9. I

The operating mechanism for each section of landing gear controlled by cables 32 and 33 comprises a disc 38 provided with sprocket teeth which mesh with the chain 39, this disc being fixedly connected with a gear 40 held rotatably in suitable bearings (not shown). The gear 4!! meshes with another gear 4| whichis mounted on a spindle 42 lodged in ball bearings 45, these bearings being held in a control box {5,3 which is attached to an arm or bracket 5| 17 extending from the rod 5!. ,A worm 44 is fixed to the spindle 42 intermediate the bearings 45 and operatively en ages a pinion 4t. whose shaft 41 is lodged in ball'bearings 48' likewise mounted in the box 43. A power transmission 49. comprising a crank arm 49a pivotally linked to a 1 connecting rod 4%. is coupled by way of a resilient lin age 5% to the sleeve 35 which holds the hub 52 of wheel 53 It will beunderstood that any rotation of the disc 38, under the conends of chain 3| are connected with a pair of cables 55 which are guided by rollers 5,6 and operate the rudder 51 (Fig. l). A chain 58 meshes with the teeth of sprocket l6 and has its ends connected with a pair of cables 59 which pass over roller 59a and control ailerons 6i! and 6|, a cable 62 serving to interconnect'the ailerons for simultaneous operation in a manner well known per se.

It should be noted that the various rollers shown, such as 34, 35, 56 and 5911, are intended to be merely representative of a system of such rollers designed to guide the various cables to the respective elements controlled thereby. It will be understood that these rollers should be so arranged as to maintain the cables under substantially constant tension irrespective of the angular position of the stick 2!], and this can be readily-accomplished by positioning the rollers in line with the fulcrum 2la thereof and, if necessary, providing additional rollers, sleeves or other guide means fixed to and swingable with the rotatable system 3, 4, 1, I3, 20,. p

The operation of the mechanism according to the invention is as follows:

When the aircraft is taxiing on the ground, any rotation of steering wheels H and I2 will be communicated to the wheels 53 so that the craft may be steered in much the same manner as an automobile. With the lever 26 manipulated so that the gear I6 is locked to the head IS, the ailerons E0 and 6| will be immobilized mechanism not further illustrated, the rod 5| will have been rotated clockwise (as viewed in Fig. 4) and gears 40 and 4| will be out of mesh; thus the actuation of cables 32, 33 will have no effect. With the lever 26 manipulated so that the gear I6 is locked to the gear l4, the ailerons 6!) and 6| will be under direct control of the wheels ll, I2 for simultaneous displacement with the rudder pivoted at-51.

Depth control is obtained by actuation of elevator fins 24 over rod 23 and stick 28, the latter oscillating about its pivot Zia when the control columns .3, 4 are rocked forward or backward. It will-be understood that rod 23 is representative of any conventional arrangement whereby the fins 24 are constrained to rock in step with the stick 20.

Prior to the take-01f it is advisable to center the controls for an instant to permit engagement of lugs H with depressions 8, the lever 26 being maintained in its position corresponding to such engagement until the craft has attained the desired altitude, whereupon the lever 26 is shifted to effect engagement of I5 with depressions ifla, coupling the gears l6 and I4 together. The reverse procedure should be observed during landing. Thus the ailerons will be locked in their neutral position on the ground as well as during the initial and final stages of a flight.

A centering of the controls should also be effected, in the case of a retractable landing gear, before the latter is to be either retracted or extended, in order to facilitate unmeshing and meshing, respectively, of the gears 40 and 4|.

' Where the landing gear is non-retractable, the

gears 40, 4| may be omitted and the disc 38 mounted directly on the spindle 42.

It will also be understood that, where the craft is equipped with a single set of controls rather than the dual controls shown in the drawing. the cross bar as well as the connecting chain 28 will be omitted and all sprockets mounted on a single shaft suitablymodified to fulfill the functions of shaft |3 and columns 3 or 4.

Accordingly, while the invention has been described with reference to a single, now preferred embodiment, it is to be understood that the invention is subject to various adaptations and modifications without departing from its spirit or exceeding its, scope as defined in the objects and in the appended claims.

What is claimed is:

1. In an aircraft, in combination, a rotatable shaft, manual control means for rotating said shaft, a landing ear including a wheel and mounting means for said wheel including a rod substantially parallel to the plane of the wheel, said wheel having a hub rotatable about said rod, and mechanism operatively linking said wheel to said shaft for rotation about said rod in response to actuation of said control means, said mechanism comprising a movable control arm and a linkage independent of said rod connecting said control arm with said hub, said linkage including a resilient link.

2. In an aircraft, in combination, a set of controls including a set of ailerons, direction control means and a manual control member, a first power transmission element, a second power transmission element displaceable relative to said.

control member, first coupling means operatively' connecting said control member with said first element, second coupling means operatively connecting said first element with said direction control means, third coupling means operatively con-- necting said second element with said ailerons, a relatively stationary member, cooperating clutch means on said first and second elements, cooperating clutch means on said second element and on said stationary member, and shifting means adapted to engage said second element alternatively with said first element for entrainment thereby and with said stationary member for relative immobilization, whereby said ailerons will either be controllable by said manual control member simultaneously with said direction control means or remain fixed in a neutral position.

3. In an aircraft, in combination, a fixed pivot, a stick swingable around said pivot, a shaft fixed to an extremity of said stick remote from said pivot, a first power transmission element rotatably mounted on said shaft, a second power transmission element rctatably and slidably mounted on said shaft, said extremity and said second element having complementary formations adapted for locking engagement, said two elements having complementar formations adapted for locking engagement, a shifting device operable to engage said second element either with said first element or with said extremity, a transverse member fixed to said shaft, a pair of control columns rotatably secured to said transverse member, manual steering means secured to said control columns, a pair of additional power transmission elements each fixed to a respective one of said third transm1ss1on means operatlvely connecting said ailerons with said second element for actuation thereby.

O Numb er 4. The combination according to claim 3 wherein said first and additional elements each comprises a sprocket having two rows of teeth, said first transmission means comprising an endless chain engaging one row of teeth of each of said sprockets.

5. The combination according to claim 4 wherein said transverse member is provided with three elongated slots traversed, respectively, by said shaft and by said control columns, said slots permitting for the displaceable mounting of said control columns and said shaft on said transverse member, whereby the tension of said chain may be adjusted.

6. The combination according to claim 3 wherein said shifting device comprises a forked lever pivotally mounted on said stick, said second element being provided with a peripheral channel engaged by the forked end of said lever.

TOMAS CARRILERO OLIVER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Capdevila July 11, 1916 Gonzalez Dec. 30, 1930 Bowers Sept. 1, 1931 Weick Mar. 8, 1938 Gerhardt et al. Nov. 1, 1938 Smith Oct. 5, 1943 Zuck 1. Mar. 18, 1947 Garehime May 25, 1948 Jamison Feb. 1, 1949 FOREIGN PATENTS Country Date Great Britain June 4, 1924 Germany June 3, 1913 Number 

